Information supplementary to the main sound broadcasting program may be transmitted on sub‑carriers located above the M and S signals. In this standard, three classes of sub‑carrier are considered:
(a) 67 kHz sub‑carrier; and
(b) 57 kHz sub‑carrier; and
(c) other sub‑carriers below 95 kHz.
Ancillary Communications Service (ACS) sub‑carriers may be used singly or in combination on condition that:
(a) the use of such sub‑carriers shall not cause interference to or degradation of the main channel or other channels; and
(b) the deviation of the main carrier due to the entire baseband signal, including all ACS signals, shall not exceed 75 kHz; and
(c) the deviation of the main carrier by any one ACS sub‑carrier alone shall not exceed 7.5 kHz.
Sub‑carrier frequencies below 57 kHz and above 95 kHz shall not be used.
67 kHz ACS sub‑carrier
Sub‑carrier frequency
The sub‑carrier frequency shall be 67 kHz 100 Hz.
Peak deviation (sub‑carrier)
For audio program and tone signals the peak deviation of the sub‑carrier shall be dependent on the highest frequency modulating the sub‑carrier in accordance with figure A2.1 (for audio program) and figure A2.2 (for audio frequency shift keyed data).
For direct FSK modulation the peak deviation of the sub‑carrier shall be dependent on the injection level of the sub‑carrier in accordance with figure A2.3 when it is directly modulated with data signals.
Pre‑emphasis
Pre‑emphasis to a time constant of 150 microseconds may be applied to an analog music or speech signal modulating the sub‑carrier (see figure A2.4).
Sideband products
Sideband products in the baseband resulting from modulation of the sub‑carrier shall not degrade the main channel L and R (or M and S) signals. Additionally, such products shall be attenuated to the extent necessary to meet the out‑of‑band and spurious emission requirements of this standard (see guideline 10). This may require attenuation of such products, when averaged in a 3 kHz bandwidth of baseband frequencies below 53 kHz and above 81 kHz, to at least 60 dB below the level of the unmodulated sub‑carrier.
57 kHz ACS sub‑carrier
Radio data system (RDS)
The 57 kHz sub‑carrier is primarily intended for use with systems complying with the specification for the Radio Data System (RDS) as published in CENELEC EN50076:1998.
Use of RDS signals
Elements of the RDS data signal intended to carry information about main program content shall be reserved for use by the broadcaster of the main sound broadcasting program service. Non‑program related data capacity of the RDS signal may be used for the transmission of supplementary information.
Non‑RDS use
57 kHz ACS services, not complying with the EN 50076 specification, may operate provided they do not cause false operation in receivers equipped with decoders for the reception of RDS signals conforming with EN 50076.
Other sub‑carriers below 95 kHz
ACS frequency
An ACS sub‑carrier frequency, other than 57 kHz or 67 kHz, may be used subject to the provisions in guideline 20.
Sideband products
Sideband products in the baseband resulting from modulation of the sub‑carrier shall not degrade the main channel L and R (or M and S) signals. Additionally, such products shall be attenuated to the extent necessary to meet the out‑of‑band and spurious emission requirements of this standard (see guideline 10). This may require attenuation of such products, when averaged in a 3 kHz bandwidth of baseband frequencies below 53 kHz and above 99 kHz, to at least 60 dB below the maximum level of the sub‑carrier.
Multiple sub‑carriers
ACS frequencies
Any combination of 57 kHz and frequencies in the range 65 to 95 kHz may be used subject to the provisions in guidelines 19 to 30.
Sideband products
Sideband products in the baseband resulting from modulation of the sub‑carriers (used singly or in combination) shall not degrade the main channel L and R (or M and S) signals. Additionally, such products shall be attenuated to the extent necessary to meet the out‑of‑band and spurious emission requirements of this standard (see guideline 10). This may require attenuation of such products, when averaged in a 3 kHz bandwidth of baseband frequencies below 53 kHz and above 99 kHz, to at least 60 dB below the maximum level of one sub‑carrier.
Table A2.1: Frequency limits of Australian FM channels
Frequency in MHz
87.6 ‑ 87.8
94.4 ‑ 94.6
101.2 ‑ 101.4
87.8 ‑88.0
94.6 ‑ 94.8
101.4 ‑ 101.6
88.0 ‑88.2
94.8 ‑ 95.0
101.6 ‑ 101.8
88.2 ‑88.4
95.0 ‑ 95.2
101.8 ‑ 102.0
88.4 ‑88.6
95.2 ‑ 95.4
102.0 ‑ 102.2
88.6 ‑88.8
95.4 ‑ 95.6
102.2 ‑ 102.4
88.8 ‑89.0
95.6 ‑ 95.8
102.4 ‑ 102.6
89.0 ‑89.2
95.8 ‑ 96.0
102.6 ‑ 102.8
89.2 ‑89.4
96.0 ‑ 96.2
102.8 ‑ 103.0
89.4 ‑89.6
96.2 ‑ 96.4
103.0 ‑ 103.2
89.6 ‑89.8
96.4 ‑ 96.6
103.2 ‑ 103.4
89.8 ‑90.0
96.6 ‑ 96.8
103.4 ‑ 103.6
90.0 ‑90.2
96.8 ‑ 97.0
103.6 ‑ 103.8
90.2 ‑90.4
97.0 ‑ 97.2
103.8 ‑ 104.0
90.4 ‑90.6
97.2 ‑ 97.4
104.0 ‑ 104.2
90.6 ‑90.8
97.4 ‑ 97.6
104.2 ‑ 104.4
90.8 ‑91.0
97.6 ‑ 97.8
104.4 ‑ 104.6
91.0 ‑91.2
97.8 ‑ 98.0
104.6 ‑ 104.8
91.2 ‑91.4
98.0 ‑ 98.2
104.8 ‑ 105.0
91.4 ‑91.6
98.2 ‑ 98.4
105.0 ‑ 105.2
91.6 ‑91.8
98.4 ‑ 98.6
105.2 ‑ 105.4
91.8 ‑92.0
98.6 ‑ 98.8
105.4 ‑ 105.6
92.0 ‑92.2
98.8 ‑ 99.0
105.6 ‑ 105.8
92.2 ‑92.4
99.0 ‑ 99.2
105.8 ‑ 106.0
92.4 ‑92.6
99.2 ‑ 99.4
106.0 ‑ 106.2
92.6 ‑92.8
99.4 ‑ 99.6
106.2 ‑ 106.4
92.8 ‑93.0
99.6 ‑ 99.8
106.4 ‑ 106.6
93.0 ‑93.2
99.8 ‑ 100.0
106.6 ‑ 106.8
93.2 ‑93.4
100.0 ‑ 100.2
106.8 ‑ 107.0
93.4 ‑93.6
100.2 ‑ 100.4
107.0 ‑ 107.2
93.6 ‑93.8
100.4 ‑ 100.6
107.2 ‑ 107.4
93.8 ‑94.0
100.6 ‑ 100.8
107.4 ‑ 107.6
94.0 ‑94.2
100.8 ‑ 101.0
107.6 ‑ 107.8
94.2 ‑94.4
101.0 ‑ 101.2
107.8 ‑ 108.0
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Figure A2.1: Maximum deviation of 67 kHz ACS sub‑carrier versus audio modulated frequency for music and voice
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Figure A2.2: Maximum deviation of 67 kHz ACS sub‑carrier versus audio modulating frequency for audio FSK
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Figure A2.3: Maximum deviation versus injection for direct FSK of 67 kHz ACS sub‑carrier
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Figure A2.4: Audio frequency pre‑emphasis characteristics for 50 and 150 microsecond time constant
Appendix 3 Emission Standard for the Australian Analog Terrestrial Television Service
The purpose of the emission standard for the Australian Analog Terrestrial Television Service is to define the parameters to be used for terrestrial broadcasting of analog television. This standard supersedes the Emission Standard for the Australian Terrestrial Television Service ‑ sixth edition (Department of Transport and Communications, March 1989).
The standard is a variant of the PAL‑B system described in ITU‑R Recommendations BT.1700, BT.1701 and BS.707.
The standard incorporates changes to channel numbering consequent to the adoption of 7 MHz channel spacing in Bands IV and V; specifications for the dual channel sound system; and line allocations in the vertical blanking interval for Teletext and closed caption data transmission.
The following characteristics are at variance with the PAL‑B standard:
(a) depth of vision modulation (see guideline 5); and
(b) use of lines in the vertical blanking interval (see guideline 19); and